In self-contained breathing apparatus (SCBA) systems, a user may carry a heavy cylinder or bottle, held to the user's body by a harness, shoulder straps, and/or waist straps. The cylinder may provide breathable air to the user via a facepiece, which may be a mask, hose, or other breathing equipment. SCBAs may be worn in dangerous environments where the ambient air is not safe to be breathed by a user.